Bike theft is on the rise again and people do different things to deter theft; we always recommend two good locks. One should be a good D lock – notice even this cycle, which is hardly top of the range, has a D lock. We recommend spending at least 10% of the value of your bike on locks. See this website for details of Sold Secure ratings of locks and a list of different ones. Remember, if your bike looks more difficult to steal than the one next to it, you’ll probably find it when you return to it.
For lots of good advice go to https://www.lcc.org.uk/pages/bike-theft-and-parking But note that this page, first published in 2011, may have some information that is out of date.
Also old, but not out of date is https://www.youtube.com/watch?v=oPDHPpnXPv8&app=desktop
GOOD
1. Ideally, use TWO secure-rated locks for maximum security
2. Lock both wheels and the frame (or wheel and frame with one lock)
3. Always lock the frame to a solid object such as a bike stand
4. Two types of lock (chain/cable and D-lock) are harder to break
5. Remove all your bike accessories every time you leave it unattended
BAD
1. Don’t leave your bike locked in a secluded location
2. Don’t lock it so it can be lifted over a post (signs can be unscrewed)
3. Don’t let your lock lie on or near the ground as it can be smashed
4. Don’t leave space inside a D-lock where tools can be inserted
Thanks to London Cycling Campaign for this information.
Courtesy of thebestbikelock.com